Three major celebrities that the company now sponsors, namely National Basketball Association star Stephen Curry, actor Dwayne "The Rock" Johnson and star ballerina Misty Copeland were among those famous names voicing concerns about his praise of Trump.

"Commentary by CEO Kevin Plank in a polarized political climate and the pointed response by Stephen Curry make it almost impossible to effectively build a cool urban lifestyle brand in the foreseeable future", the analyst, Susquehanna International Group's Sam Poser, wrote in a research note Wednesday. "In this case, perception is reality", analyst Sam Poser wrote in a note to clients Wednesday.

Poser cited the "reputational risk" and "sloppy management commentary in a polarized political environment". "You have to take that into account when you buy it".

The noise got so loud that Plank took out a full-page newspaper ad on Wednesday assuring the athletes, employees, and his customers, that they shouldn't equate his comments praising Trump's economic policies with the president's views on more-controversial measures, such as the now-frozen executive order on immigration.

Some Plank comments in a CNBC interview earlier this month, that Trump is "pro-business" and a "real asset", drew ire from customers and big-name endorsers. "So there's a lot that I respect there".

Golden State Warriors" Steph Curry said he agreed with Plank's description of Trump "if you remove the "et'" from asset. "I want to clarify for our hometown exactly the values for which Under Armour and I stand". "When a sports figure becomes engaged, it takes the story to an entirely different level".

Nearly immediately after Plank's comments, a #BoycottUnderArmour hashtag appeared. In its most recent quarterly earnings report, the company reported a significant slow-down in its sales, predicted slower revenue growth in 2017, and announced a leadership shake-up in its senior ranks. But the stock is down more than 25% this year, largely due to awful earnings and a poor outlook that it reported at the end of last month.